Method and apparatus for managing communication operations in orthogonal frequency division multiplexing system

ABSTRACT

Accordingly, the invention provides a method and apparatus for managing communication operations in an Orthogonal Frequency Division Multiplexing (OFDM) system. Further the method includes generating, by a first OFDM apparatus ( 100 ), a signal comprising data and at least one of a Reference Signal (RS) and a message, the signal is generated by repeating the at least one of the RS and the message over a set of OFDM symbols using a resource mapper, performing an Inverse Fourier Transform operation (IFFT) according to a numerology of a first OFDM apparatus, adding a Cyclic Prefix (CP) to the data, and adding a block CP to the at least one of the repeated RS and the message. Further, the method includes transmitting, by the first OFDM apparatus ( 100 ), the signal to a second OFDM apparatus ( 200 ).

FIELD OF THE INVENTION

The present invention relates to a wireless communication system, andmore specifically relates to a method and apparatus for managingcommunication operations in an Orthogonal Frequency DivisionMultiplexing (OFDM) system. The present application is based on, andclaims priority from an Indian Application Number 201841036605 filed on27 Sep. 2018, the disclosure of which is hereby incorporated byreference herein.

BACKGROUND OF INVENTION

A fourth-generation (4G) long term evolution (LTE) and afifth-generation (5G) new radio (NR) technologies use orthogonalfrequency division multiplexing (OFDM) based air interface for multipleaccess. An OFDM node transmits OFDM symbols with subcarrier spacingdependent symbol duration. This symbol duration decreases with increasein the subcarrier spacing. The LTE uses 15 kHz as the subcarrier spacingfor a data transmission whereas the NR allows multiple subcarrierspacing for the data transmission. A system that allows multiplesubcarrier spacing is called multiple numerology system. Generally,symbol boundaries are expected to be aligned for detection of a receivedsignal, otherwise, it may lead to detection of errors. However, if areceive node is not time-synchronized with a transmit node, and/or ifthe transmit node and the receive node are using different subcarrierspacing, then the symbol boundaries may not be aligned at a receiver.The mismatch or misalignment is either due to propagation delay and/ordue to the receiver processing with different numerology. This is termedhere as asynchronous transmission and reception. Therefore, there is aneed for a transceiver to be designed to enable asynchronoustransmission and reception. Examples of asynchronous reception areinterference occurring from an unsynchronised interfering node and thereceiver processing with different numerology than that of atransmitter.

A node transmits messages, which can be received by other nodes within anetwork. In the network that uses multiple numerologies, it is possiblethat the message transmitted with one numerology is received by thenodes using different numerologies. Example being a node broadcasting amessage using 15 kHz subcarrier spacing can be received and decoded bythe nodes using the numerologies 15 kHz, 30 kHz, 60 kHz, etc., andvice-versa. The transmitted signal includes a broadcast message,multicast message, unicast message, control information, referencesignal for interference measurement, etc.

Base station to base station (BS-to-BS) interference is a well-knownproblem in time division duplex (TDD) networks when an uplink (UL) and adownlink (DL) are not aligned across the cells in the same and adjacentbands. Traditionally, it is solved by adopting the same DL:UL ratioacross networks in a time-synchronous manner, additional guard time,etc. However, this method leads to inefficiencies in heterogeneousscenario due to the different traffic requirement of each BSs, henceaffects the network performance and throughput. As shown in FIG. 1, Node1 is performing the DL transmission to Node 3, while Node 4 isperforming the UL transmission to Node 2 in the same time-frequencyresources. As a result, the DL from the Node 1 will cause interferenceto the desired UL signal from the node 4 at the Node 2. Besides that,the BS to BS interference might also be prominent when the DL signalfrom the Node 1 will reach the Node2 when a propagation delay exceeds agap period between the DL to UL transition even if the network issynchronized. Depending on the distance between the Node 1 and the Node2, at least two scenarios arise such as,

-   -   i. When two nodes are near to each other, an interfering signal        from one node will be received by another node with the slot        boundaries of the interfering signal and a desired signal is        either aligned with each other or with misalignment within the        cyclic prefix (CP) duration. When the interfering signal and the        desired signals use different numerology, different numerology        leads to degraded system performance, and therefore need        interference mitigation schemes. For e.g., interference between        BS and user equipment (UE), relay and UE, etc. The interference        between nodes of the same type is called cross-link interference        (CLI), and cross-link interference occurs when the dynamic DL:UL        ratio is used by BSs in TDD system, or in in-band full-duplex        systems. For e.g., CLI can be between BS to BS, relay to relay,        UE to UE, etc. For e.g., Node 1 is transmitting at 30 kHz        numerology, Node 3 is receiving at 30 kHz numerology while Node        2 is receiving at 15 kHz numerology.    -   ii. When the nodes are far away from each other (remote nodes),        then the propagation delay between them is higher than CP.        sometimes higher than OFDM symbol duration itself. This cause's        interference signal from one node to another node with the slot        boundaries of the interfering signal and the desired signal are        completely misaligned. One such remote interference is due to        the tropospheric ducting as mentioned in FIG. 1.

Thus, it is desired to address the above-mentioned disadvantages orother shortcomings or at least provide a useful alternative.

OBJECT OF THE INVENTION

The principal object of the embodiments herein is to provide a methodand apparatus for managing communication operations in an OrthogonalFrequency Division Multiplexing system (OFDM).

Another object of the invention is to generate a signal comprising dataand at least one of a Reference Signal (RS) and a message by repeatingthe at least one of the RS and the message over a set of OFDM symbolsusing a resource mapper, performing an Inverse Fourier Transformoperation (IFFT) according to a numerology of a first OFDM apparatus,adding a Cyclic Prefix (CP) to the data, and adding a block CP to the atleast one of the repeated RS and the message.

Another object of the invention is to generate the signal comprisingdata and at least one of the RS and the message by repeating the atleast one of the RS and the message over the set of OFDM symbols usingthe resource mapper with a phase rotation, performing the IFFT operationaccording to the numerology of the first OFDM apparatus, and adding thecyclic prefix.

Another object of the invention is to transmit the signal to a secondOFDM apparatus.

Another object of the invention is to estimate an interference bymonitoring consecutive slots or symbols for the interference.

Another object of the invention is to detect estimated interference inthe slots or symbols being monitored meets a predefined threshold set bya network entity or by the first OFDM apparatus.

Another object of the invention is to mitigate the interference byperforming one of adjusting a Guard Period (GP), adjusting a UL power,adjusting a DL power, switching to a bandwidth part (BWP), tilting adirection of a beam to avoid the interference, and nullifying a beam ina direction of incoming interference.

Another object of the invention is to receive the signal comprising dataand at least one of the RS and the message from the first OFDMapparatus.

Another object of the invention is to filter a desired band containingat least one of the RS and the message from the reference signal.

Another object of the invention is to remove the cyclic prefix from thesignal and decode at least one of the RS and the message from the signalwith adjusting a circular shift in the set of symbol.

BRIEF SUMMARY OF THE INVENTION

Accordingly, the invention provides a method and apparatus for managingcommunication operations in an Orthogonal Frequency DivisionMultiplexing (OFDM) system. Further the method includes generating, by afirst OFDM apparatus, a signal comprising data and at least one of aReference Signal (RS) and a message, the signal is generated byrepeating the at least one of the RS and the message over a set of OFDMsymbols using a resource mapper, performing an Inverse Fourier Transformoperation (IFFT) according to a numerology of a first OFDM apparatus,adding a Cyclic Prefix (CP) to the data, and adding a block CP to the atleast one of the repeated RS and the message. Further, the methodincludes transmitting, by the first OFDM apparatus, the signal to asecond OFDM apparatus.

Accordingly, the invention provides a method and apparatus for managingcommunication operations in an OFDM system. Further the method includesgenerating, by a first OFDM apparatus, a signal comprising data and atleast one of a RS and a message, the signal is generated by repeatingthe at least one of the RS and the message over a set of OFDM symbolsusing a resource mapper with a phase rotation, performing an IFFTaccording to a numerology of a first OFDM apparatus, and adding a CP tothe data. Further, the method includes transmitting, by the first OFDMapparatus, the signal to a second OFDM apparatus.

Accordingly, the invention provides a method and apparatus for managingcommunication operations in an OFDM system. Further, the method includesreceiving, by a second OFDM apparatus, a signal comprising data and atleast one of a RS and a message from a first OFDM apparatus, wherein theRS and the message are repeated over a set of OFDM symbols. Further, themethod includes filtering, by the second OFDM apparatus, a desired bandcontaining at least one of the RS and the message from the referencesignal. Further, the method includes removing, by the second OFDMapparatus, a cyclic prefix from the signal. Further, the method includesdecoding, by a second OFDM apparatus, at least one of the RS and themessage from the signal with adjusting a circular shift in the set ofsymbol.

Further, the method includes estimating, by the second OFDM apparatus,an interference by monitoring consecutive slots or symbols for theinterference. Further, the method includes detecting, by the second OFDMapparatus, estimated interference in the slots or symbols beingmonitored meets a predefined threshold set by a network entity or by thefirst OFDM apparatus. Further, the method includes mitigating, by thesecond OFDM apparatus, the interference by performing one of adjusting aGP, adjusting a UL power, adjusting a DL power, switching to a BWP,tilting a direction of a beam to avoid the interference, and nullifyinga beam in a direction of incoming interference.

These and other aspects of the embodiments herein will be betterappreciated and understood when considered in conjunction with thefollowing description and the accompanying drawings. It should beunderstood, however, that the following descriptions, while indicatingpreferred embodiments and numerous specific details thereof, are givenby way of illustration and not of limitation. Many changes andmodifications may be made within the scope of the embodiments hereinwithout departing from the spirit thereof, and the embodiments hereininclude all such modifications.

DESCRIPTION OF THE DRAWINGS

This invention is illustrated in the accompanying drawings, throughoutwhich like reference letters indicate corresponding parts in the variousfigures. The embodiments herein will be better understood from thefollowing description with reference to the drawings, in which:

FIG. 1 illustrates an interference due to tropospheric ducting,according to a prior art;

FIG. 2A illustrates a block diagram of a first OFDM apparatus formanaging communication operations in an Orthogonal Frequency DivisionMultiplexing (OFDM) system, according to an embodiment as disclosedherein;

FIG. 2B illustrates a block diagram of a processor of the first OFDMapparatus, according to an embodiment as disclosed herein;

FIG. 3A is a flow diagram illustrating a transmitting method formanaging communication operations in the OFDM system, according to anembodiment as disclosed herein;

FIG. 3B is a flow diagram illustrating a method for generating a signalusing a resource mapper, according to an embodiment as disclosed herein;

FIG. 3C illustrates a Reference Signal (RS) with a block Cyclic Prefix(CP) transmitter chain, according to embodiments as disclosed herein;

FIG. 4A is a flow diagram illustrating another transmitting method formanaging communication operations in the OFDM system, according to anembodiment as disclosed herein;

FIG. 4B is a flow diagram illustrating a method for generating a signalusing a resource mapper with a phase rotation, according to anembodiment as disclosed herein;

FIG. 4C illustrates the RS with a circular shift transmitter chain,according to embodiments as disclosed herein;

FIG. 4D illustrates effect of taking an Inverse Fourier Transform (IFFT)and adding CP to a phase rotated repeated sequences, according toembodiments as disclosed herein;

FIG. 5A illustrates a block diagram of a second OFDM apparatus formanaging communication operations in the OFDM system, according to anembodiment as disclosed herein;

FIG. 5B illustrates a block diagram of a processor of the second OFDMapparatus, according to an embodiment as disclosed herein;

FIG. 5C is a flow diagram illustrating a receive method for managingcommunication operations in the OFDM system, according to an embodimentas disclosed herein;

FIG. 5D illustrates receiver chain with respect to the RS, according toembodiments as disclosed herein;

FIG. 5E illustrates a receiver processing samples, according toembodiments as disclosed herein;

FIG. 6 illustrates a transmit and receive chain for RS transmission inhigher numerology as compared to reception, according to embodiments asdisclosed herein;

FIG. 7 illustrates a transmit and receive chain for RS transmission inlower numerology as compared to reception, according to embodiments asdisclosed herein; and

FIG. 8 illustrates a slot structure of four base stations (BS) to aid aninterference measurement, according to embodiments as disclosed herein.

DETAILED DESCRIPTION OF THE INVENTION

The embodiments herein and the various features and advantageous detailsthereof are explained more fully with reference to the non-limitingembodiments that are illustrated in the accompanying drawings anddetailed in the following description. Descriptions of well-knowncomponents and processing techniques are omitted so as to notunnecessarily obscure the embodiments herein. Also, the variousembodiments described herein are not necessarily mutually exclusive, assome embodiments can be combined with one or more other embodiments toform new embodiments. The term “or” as used herein, refers to anon-exclusive or, unless otherwise indicated. The examples used hereinare intended merely to facilitate an understanding of ways in which theembodiments herein can be practiced and to further enable those skilledin the art to practice the embodiments herein. Accordingly, the examplesshould not be construed as limiting the scope of the embodiments herein.

As is traditional in the field, embodiments may be described andillustrated in terms of blocks which carry out a described function orfunctions. These blocks, which may be referred to herein as units ormodules or the like, are physically implemented by analog or digitalcircuits such as logic gates, integrated circuits, microprocessors,microcontrollers, memory circuits, passive electronic components, activeelectronic components, optical components, hardwired circuits, or thelike, and may optionally be driven by firmware and software. Thecircuits may, for example, be embodied in one or more semiconductorchips, or on substrate supports such as printed circuit boards and thelike. The circuits constituting a block may be implemented by dedicatedhardware, or by a processor (e.g., one or more programmedmicroprocessors and associated circuitry), or by a combination ofdedicated hardware to perform some functions of the block and aprocessor to perform other functions of the block. Each block of theembodiments may be physically separated into two or more interacting anddiscrete blocks without departing from the scope of the invention.Likewise, the blocks of the embodiments may be physically combined intomore complex blocks without departing from the scope of the invention.

The accompanying drawings are used to help easily understand varioustechnical features and it should be understood that the embodimentspresented herein are not limited by the accompanying drawings. As such,the present disclosure should be construed to extend to any alterations,equivalents and substitutes in addition to those which are particularlyset out in the accompanying drawings. Although the terms first, second,etc. may be used herein to describe various elements, these elementsshould not be limited by these terms. These terms are generally onlyused to distinguish one element from another.

Accordingly, the invention provides a method and apparatus for managingcommunication operations in an Orthogonal Frequency DivisionMultiplexing (OFDM) system. Further, the method includes generating, bya first OFDM apparatus, a signal comprising data and at least one of aReference Signal (RS) and a message. Further, the method includestransmitting the signal to a second OFDM apparatus. Further, the methodincludes estimating, by a second OFDM apparatus, an interference bymonitoring consecutive slots or symbols for the interference. Further,the method includes detecting, by the second OFDM apparatus, estimatedinterference in the slots or symbols being monitored meets a predefinedthreshold set by a network entity or by the first OFDM apparatus.Further the method includes mitigating, by the second OFDM apparatus,the interference by performing one of adjusting a Guard Period (GP),adjusting an uplink (UL) power, adjusting a downlink (DL) power,switching to a bandwidth part (BWP), tilting a direction of a beam toavoid the interference, and nullifying a beam in a direction of incominginterference.

Referring now to the drawings, and more particularly to FIGS. 2A through8, where similar reference characters denote corresponding featuresconsistently throughout the figures, there are shown preferredembodiments.

FIG. 2A illustrates a block diagram of a first OFDM apparatus (100) formanaging communication operations in an Orthogonal Frequency DivisionMultiplexing (OFDM) system, according to an embodiment as disclosedherein. In an embodiment, the first OFDM apparatus (100) includes amemory (110), a processor (120), and a communicator (130). The firstOFDM apparatus (100) can be, for example, but not limited to asmartphone, base station or a like.

The memory (110) also stores instructions to be executed by theprocessor (120). The memory (110) may include non-volatile storageelements. Examples of such non-volatile storage elements may includemagnetic hard discs, optical discs, floppy discs, flash memories, orforms of electrically programmable memories (EPROM) or electricallyerasable and programmable (EEPROM) memories. In addition, the memory(110) may, in some examples, be considered a non-transitory storagemedium. The term “non-transitory” may indicate that the storage mediumis not embodied in a carrier wave or a propagated signal. However, theterm “non-transitory” should not be interpreted that the memory (110) isnon-movable. In some examples, the memory (110) can be configured tostore larger amounts of information than the memory. In certainexamples, a non-transitory storage medium may store data that can, overtime, change (e.g., in Random Access Memory (RAM) or cache).

The processor (120) communicates with the memory (110), and thecommunicator (130). In an embodiment, the memory (110) can be aninternal storage unit or it can be an external storage unit of the firstOFDM apparatus (100), a cloud storage, or any other type of externalstorage. The processor (120) is configured to execute instructionsstored in the memory (110) and to perform various processes.

In an embodiment, the processor (120) is configured to generate a signalcomprising data and at least one of a Reference Signal (RS) and amessage, wherein the signal is generated by repeat the at least one ofthe RS and the message over a set of OFDM symbols using a resourcemapper, perform an Inverse Fourier Transform operation (IFFT) accordingto a numerology of the first OFDM apparatus (100), add a Cyclic Prefix(CP) to the data, and add a block CP to the at least one of the repeatedRS and the message. Further, the processor (120) is configured totransmit the signal to a second OFDM apparatus (200).

In an embodiment, the block CP is derived by adding one CP to the set ofOFDM symbols. In an embodiment, a block CP length to the set of OFDMsymbols is scaled by number of repetitions.

In an embodiment, repeating the at least one of the RS or the messageover the set of OFDM symbols comprises transmit at least one of the RSand the message in a first symbol of the set of OFDM symbols and repeatat least one of the same RS and the same message in consecutive symbols.

In an embodiment, symbol boundaries of the set of OFDM symbols are notin sync with the second OFDM apparatus (200), when the signal isreceived at the second OFDM apparatus (200).

In an embodiment, repeating the at least one of the RS or the messageover the set of OFDM symbols includes determining whether the numerologyat the first OFDM apparatus (100) is one of same as numerology at thesecond OFDM apparatus (200), higher that the numerology at the secondOFDM apparatus (200), and lower that the numerology at the second OFDMapparatus (200), and performing one of repeating the at least one of theRS and the message over the set of OFDM symbols when the numerology atthe first OFDM apparatus (100) is same as the numerology at the secondOFDM apparatus (200), wherein the set of OFDM symbols are greater thanone and is transmitted with the block CP for all the set of OFDMsymbols, repeating the at least one of the RS and the message over theset of OFDM symbols when the numerology at the first OFDM apparatus(100) is higher than the numerology at the second OFDM apparatus (200),wherein the set of OFDM symbols depends on a ratio of the numerology ofthe first OFDM apparatus (100) to the numerology of the second OFDMapparatus (200), and interleaving the at least one of the RS and themessage in a frequency domain and repeating the at least one of the RSand the message over the set of OFDM symbols when the numerology at thefirst OFDM apparatus (100) is lower than the numerology at the secondOFDM apparatus (200), wherein the interleaving is performed based on theratio of the numerology of the first OFDM apparatus (100) to thenumerology of the second OFDM apparatus (200).

In an embodiment, at least one of the RS and the message is spread overa predefined bandwidth, wherein the predefined bandwidth is in multipleof Resource Blocks (RBs) fully or partially span over a configuredbandwidth, and wherein the RBs are allocated in a consecutive manner ora continuous manner to avoid possible contamination of reception.

In an embodiment, the set of OFDM symbols is determined as a function ofat least one of the numerology used at the first OFDM apparatus (100),the numerology used at the second OFDM apparatus (200), and apropagation delay.

In an embodiment, adding a node identifier in a sequence used forgenerating the RS to identify an interference at the second OFDMapparatus (200), wherein the node identifier indicates at least one ofan interfering node, a group of interfering nodes, a cell, and aninterference level.

In an embodiment, the interference level indicates at least one of aremote interference and a cross-link interference.

In an embodiment, the RS is transmitted orthogonally in at least one ofa code, the frequency domain, a time domain, and a space domain acrossvarious nodes in the OFDM system, based on the node identifier and aninterference level and a number of affected symbols.

In an embodiment, in the time domain, the orthogonality is achieved byone of a node transmits the RS at one-time unit while all the othernodes are receiving the RS and a node receives the RS at one instantwhile all other nodes are transmitting the RS.

In an embodiment, the node identifier is associated with one of thefirst OFDM apparatus (100) indicating that the first OFDM apparatus(100) is facing the interference from the second OFDM apparatus (200),and the first OFDM apparatus (100) indicating that the first OFDMapparatus (100) is a source of interference for the second OFDMapparatus (200).

In an embodiment, the remote interference, at least one of the firstOFDM apparatus (100) and a group of first OFDM apparatus (100), isdetected when an Interference over Thermal (IOT) meets a predefinedthreshold, wherein the IOT is the interference level measured above athermal noise level.

In an embodiment, the number of affected symbols in a transmission isdetermined at least one of the first OFDM apparatus (100) from the groupof first OFDM apparatus (100) based on at least one of IOT value and asignal to interference plus noise ratio (SINR).

In an embodiment, the number of affected symbols are included in asequence for generation of a RS to be transmitted from the first OFDMapparatus (100).

In an embodiment, at least one of the first OFDM apparatus (100) and thesecond OFDM apparatus (200) is configured to transmit the RS in ameasurement window comprising a set of one of symbols and slotsdetermined by network based on the interference level, and the number ofaffected symbols, and wherein the measurement window includes DL-to-ULtransition point.

In an embodiment, the RS is transmitted from at least of the first OFDMapparatus (100) and the second OFDM apparatus (200) at a beginning ofthe measurement window configured by the network.

In an embodiment, the RS is received in at least one of the first OFDMapparatus (100) and the second OFDM apparatus (200) at last N symbols ofthe measurement window configured by the network, wherein the N symbolsare configured by a higher layer.

The communicator (130) is configured for communicating internallybetween internal hardware components and with external devices via oneor more networks.

Although the FIG. 2A shows various hardware components of the first OFDMapparatus (100) but it is to be understood that other embodiments arenot limited thereon. In other embodiments, the first OFDM apparatus(100) may include less or more number of components. Further, the labelsor names of the components are used only for illustrative purpose anddoes not limit the scope of the invention. One or more components can becombined together to perform the same or substantially similar functionto manage communication operations in the OFDM system.

FIG. 2B illustrates a block diagram of the processor (120) of the firstOFDM apparatus (100), according to an embodiment as disclosed herein. Inan embodiment, the processor (120) includes a resource mapper (121), anIFFT converter (122), a cyclic controller (123), and a RS and messagetransmitter (124).

The resource mapper (121) repeats the at least one of the RS and themessage over the set of OFDM symbols. The IFFT converter (122) performsIFFT operation according to the numerology of the first OFDM apparatus(100). The cyclic controller (123) adds the CP to the data and adds theblock CP to the at least one of the repeated RS and the message.

The RS and message transmitter (124) transmits the signal to the secondOFDM apparatus (200).

FIG. 3A is a flow diagram 300 illustrating a transmitting method formanaging communication operations in the OFDM system, according to anembodiment as disclosed herein. The operations (302-304) are performedby the first OFDM apparatus (100).

At 302, the method includes generating the signal comprising data and atleast one of the RS and the message. At 304, the method includestransmitting the signal to the second OFDM apparatus (200).

FIG. 3B is a flow diagram 302 illustrating a method for generating asignal using a resource mapper, according to an embodiment as disclosedherein. The operations (302 a-302 d) are performed by the first OFDMapparatus (100).

At 302 a, the method includes repeating the at least one of the RS andthe message over the set of OFDM symbols using the resource mapper(121). At 302 b, the method includes performing the IFFT operationaccording to the numerology of the first OFDM apparatus (100). At 302 c,the method includes adding the CP to the data. At 302 d, the methodincludes adding the block CP to the at least one of the repeated RS andthe message.

FIG. 3C illustrates the RS with the block CP transmitter chain,according to embodiments as disclosed herein. Transmit signal design forasynchronous detection for a transceiver. The transmit signal whichconsists of RS and/or broadcast message or any other message, that needsto be asynchronously detected at the receiver is generated and detectedas described below. Repetition of information over ‘M’ symbols.

In an embodiment, the RS or message is repeated over ‘M’ symbols wherethe ‘M’ is greater than one and transmitted with a block CP for all theM symbols. FIG. 3C shows an example of RS transmission. The RS in thefigure can be substituted by any other message to be transmitted.

FIG. 4A is a flow diagram 400 illustrating another transmitting methodfor managing communication operations in the OFDM system, according toan embodiment as disclosed herein. The operations (402-404) areperformed by the first OFDM apparatus (100).

At 402, the method includes generating a signal comprising data and atleast one of a Reference Signal (RS) and a message. At 404, the methodincludes transmitting the signal to a second OFDM apparatus (200).

FIG. 4B is a flow diagram 402 illustrating a method for generating thesignal using the resource mapper (121) with a phase rotation, accordingto an embodiment as disclosed herein. The operations (402 a-402 c) areperformed by the first OFDM apparatus (100)

At 402 a, the method includes repeating the at least one of the RS andthe message over a set of OFDM symbols using the resource mapper (121)with the phase rotation. At 402 b, the method includes performing anInverse Fourier Transform operation (IFFT) according to a numerology ofthe first OFDM apparatus (100). At 402 c, the method includes adding aCyclic Prefix (CP) to the data.

In an embodiment, the phase rotation is performed to maintain a timedomain circularity over a symbol at the second OFDM apparatus (200).

In an embodiment, repeating the at least one of the RS or the messageover the set of OFDM symbols comprises transmit at least one of the RSand the message in a first symbol of the set of OFDM symbols without thephase rotation and repeat at least one of the same RS and the samemessage in consecutive symbols with the phase rotation.

In an embodiment, repeating the at least one of the RS or the messageover the set of OFDM symbols comprises transmit at least one of the RSand the message the set of OFDM symbols with the phase rotation except alast symbol of the set of OFDM symbols, wherein the last symbol of theset of OFDM symbols is filled without the phase rotation.

In an embodiment, symbol boundaries of the set of OFDM symbols are notin sync with the second OFDM apparatus (200), when the signal isreceived at the second OFDM apparatus (200).

In an embodiment, repeating the at least one of the RS and the messageover the set of OFDM symbols comprises performing one of repeating theat least one of the RS and the message over the set of OFDM symbols whenthe numerology at the first OFDM apparatus (100) is same as thenumerology at the second OFDM apparatus (200), wherein the set of OFDMsymbols are greater than one, repeating the at least one of the RS andthe message over the set of OFDM symbols when the numerology at thefirst OFDM apparatus (100) is higher than the numerology at the secondOFDM apparatus (200), wherein the set of OFDM symbols depends on a ratioof the numerology of the first OFDM apparatus (100) to the numerology ofthe second OFDM apparatus (200), and interleaving the at least one ofthe RS and the message in a frequency domain and repeating the at leastone of the RS and the message over the set of OFDM symbols when thenumerology at the first OFDM apparatus (100) is lower than thenumerology at the second OFDM apparatus (200), wherein the interleavingis performed based on the ratio of the numerology of the first OFDMapparatus (100) to the numerology of the second OFDM apparatus (200).

In an embodiment, at least one of the RS and the message is spread overa predefined bandwidth, wherein the predefined bandwidth is in multipleof Resource Blocks (RBs) fully or partially span over a configuredbandwidth, and wherein the RBs are allocated in a consecutive manner ora continuous manner to avoid possible contamination of reception.

In an embodiment, the set of OFDM symbols is determined as a function ofat least one of the numerology used at the first OFDM apparatus (100),the numerology used at the second OFDM apparatus (200), and apropagation delay.

In an embodiment, adding a node identifier in a sequence used forgenerating the RS to identify the interference at the second OFDMapparatus (200), wherein the node identifier indicates at least one ofan interfering node, a group of interfering nodes, a cell, and aninterference level, wherein the interference is one of a remoteinterference and a cross-link interference.

In an embodiment, the sequence used for generating the RS is transmittedorthogonally in at least one of a code, the frequency domain, the timedomain, and a space domain across various nodes in the OFDM system,based on the at least one of the node identifier and an interferencelevel and a number of affected symbols.

In an embodiment, in the time domain, the orthogonality is achieved byone of a node transmits the RS at one-time unit while all the othernodes are receiving the RS and a node receives the RS at one instantwhile all other nodes are transmitting the RS.

In an embodiment, the node identifier is associated with one of thefirst OFDM apparatus (100) indicating that the first OFDM apparatus(100) is facing the interference from the second OFDM apparatus (200),and the interfering node indicating that the interfering node is causingthe interference at the first OFDM apparatus (100).

In an embodiment, the remote interference at the first OFDM apparatus(100) is detected when an Interference over Thermal (TOT) meets apredefined threshold, wherein the IOT is the interference level measuredabove a thermal noise level at the second OFDM apparatus (200).

In an embodiment, the number of affected symbols in a transmission isdetermined at, at least one of the first OFDM apparatus (100) from thegroup of first OFDM apparatus (100) based on at least one of IOT valueand a signal to interference plus noise ratio (SINR).

In an embodiment, the number of affected symbols are included in the atleast one RS.

In an embodiment, the at least one RS is configured in a fixedmeasurement window in terms of symbols or slots, and wherein themeasurement window derived at a point where one of a DL-to-UL transitionor a DL-to-UL transition occurs.

In an embodiment, the at least one RS is reported at a beginning of themeasurement window.

FIG. 4C illustrates the RS with a circular shift transmitter chain,according to embodiments as disclosed herein. Another embodiment is totransmit the RS or message in the first symbol and repeat the same inconsecutive M−1 symbols with a phase rotation as given in equation (1).FIG. 4C shows the transmitter chain for this method for RS transmission.As a result, after taking IFFT and adding CP, the time domain sequencewill be repeated as shown in FIG. 4D for CP length of 2 samples. Thedetailed description is given in the FIG. 4D.

FIG. 4D illustrates effect of taking the IFFT and adding CP to the phaserotated repeated sequences, according to embodiments as disclosedherein. The information to be filled in each OFDM symbol is given below.R^(m) is the information to be filled in the m^(th) OFDM symbol, i isthe subcarrier index, X is the information like the actual message orthe base sequence of RS, L is the number of samples in CP and N_(FFT)^(T) is the FFT size at the transmitter.

$\begin{matrix}{R_{i}^{m} = {X_{i}e^{\frac{j\; 2\;\pi\;{mLi}}{N_{FFT}^{T}}}}} & (1)\end{matrix}$

The RS or message are spread over a predefined bandwidth. The bandwidthis in multiple resource blocks (RB) span over the configured bandwidthfully or partially. The RBs are allocated in a consecutive or continuousmanner to avoid possible contamination of while reception. M is afunction of numerology used at the transmitter, numerology used at thereceiver, propagation delay.

FIG. 5A illustrates a block diagram of a second OFDM apparatus (200) formanaging communication operations in the OFDM system, according to anembodiment as disclosed herein. In an embodiment, the second OFDMapparatus (200) includes a memory (210), a processor (220), and acommunicator (230). The second OFDM apparatus (200) can be, for example,but not limited to a smartphone, base station or a like.

The memory (210) also stores instructions to be executed by theprocessor (220). The memory (210) may include non-volatile storageelements. Examples of such non-volatile storage elements may includemagnetic hard discs, optical discs, floppy discs, flash memories, orforms of electrically programmable memories (EPROM) or electricallyerasable and programmable (EEPROM) memories. In addition, the memory(210) may, in some examples, be considered a non-transitory storagemedium. The term “non-transitory” may indicate that the storage mediumis not embodied in a carrier wave or a propagated signal. However, theterm “non-transitory” should not be interpreted that the memory (210) isnon-movable. In some examples, the memory (210) can be configured tostore larger amounts of information than the memory. In certainexamples, a non-transitory storage medium may store data that can, overtime, change (e.g., in Random Access Memory (RAM) or cache).

The processor (220) communicates with the memory (210), and thecommunicator (230). In an embodiment, the memory (210) can be aninternal storage unit or it can be an external storage unit of thesecond OFDM apparatus (200), a cloud storage, or any other type ofexternal storage. The processor (220) is configured to executeinstructions stored in the memory (210) and to perform variousprocesses.

In an embodiment, the processor (220) is configured to receive a signalcomprising data and at least one of a Reference Signal (RS) and amessage from a first OFDM apparatus (100), wherein the RS and themessage is repeated over the set of OFDM symbols. Further, the processor(220) is configured to filter a desired band containing at least one ofthe RS and the message from the reference signal. Further, the processor(220) is configured to remove a cyclic prefix from the signal. Further,the processor (220) is configured to decode at least one of the RS andthe message from the signal with adjusting a circular shift in the setof symbol.

Further, the processor (220) is configured to estimate an interferenceby monitoring consecutive slots or symbols for the interference.Further, the processor (220) is configured to detect the estimatedinterference in the slots or symbols being monitored meets a predefinedthreshold set by a network entity or by the second OFDM apparatus (200).Further, the processor (220) is configured to mitigate the interferenceby performing one of adjusting a Guard Period (GP), adjusting a ULpower, adjusting a DL power, switching to a bandwidth part (BWP),tilting a direction of a beam to avoid interference, and nullifying abeam in a direction of incoming interference.

In an embodiment, a circular shift in the set of symbol is determinedand compensated to detect original transmitted information from thesignal when a frequency domain correlation is used to detect a sequenceof the RS.

In an embodiment, decoding the at least one of the RS and the messagefrom the signal using the FFT operation according to the numerology ofthe second OFDM apparatus (200).

In an embodiment, determining at least one of an interfering node and aninterference level based on a node identifier indicated in a sequenceused for generating the RS.

In an embodiment, the at least one of the RS and the message is spreadover a predefined bandwidth, wherein the predefined bandwidth is inmultiple of group of Resource Blocks (RBs) fully or partially span overa configured bandwidth, wherein the group of RBs are allocated in aconsecutive manner or a continuous manner to avoid possiblecontamination of reception.

In an embodiment, the set of OFDM symbols is determined as a function ofat least one of the numerology used at the first OFDM apparatus (100),the numerology used at the second OFDM apparatus (200), and apropagation delay.

In an embodiment, the node identifier is associated with one of thefirst OFDM apparatus (100) indicating that the first OFDM apparatus(100) is facing the interference from the second OFDM apparatus (200),and the interfering node indicating that the interfering node is causingthe interference at the first OFDM apparatus (100).

In an embodiment, terminating the estimation of the interference whenthe second OFDM apparatus (200) is not able to observe the at least oneRS in a measurement period.

The communicator (230) is configured for communicating internallybetween internal hardware components and with external devices via oneor more networks.

Although the FIG. 5A shows various hardware components of the secondOFDM apparatus (200) but it is to be understood that other embodimentsare not limited thereon. In other embodiments, the second OFDM apparatus(200) may include less or more number of components. Further, the labelsor names of the components are used only for illustrative purpose anddoes not limit the scope of the invention. One or more components can becombined together to perform the same or substantially similar functionfor managing communication operations in the OFDM system.

FIG. 5B illustrates a block diagram of the processor (220) of the secondOFDM apparatus (200), according to an embodiment as disclosed herein. Inan embodiment, the processor (220) includes a desired band controller(221), a FFT converter (222), a cyclic controller (223), an interferencedetector (224), an interference mitigater (225), and RS and messagereceiver (226).

In an embodiment, the desired band controller (221) filters the desiredband containing at least one of the RS and the message from thereference signal. The FFT converter (222) performs FFT operationaccording to the numerology of the second OFDM apparatus (200). Thecyclic controller (223) removes the cyclic prefix from the signal. Theinterference detector (224) estimates the interference by monitoringconsecutive slots or symbols for the interference. Further, theinterference detector (224) detects the estimated interference in theslots or symbols being monitored meets the predefined threshold set by anetwork entity or by the second OFDM apparatus (200).

In an embodiment, the interference mitigater (225) mitigates theinterference by performing one of adjusting the GP, adjusting the ULpower, adjusting the DL power, switching to the BWP, tilting thedirection of a beam to avoid interference, and nullifying the beam inthe direction of incoming interference. The RS and message receiver(226) receive the signal comprising data and at least one of the RS andthe message from the first OFDM apparatus (100), wherein the RS and themessage is repeated over the set of OFDM symbols.

FIG. 5C is a flow diagram 500 illustrating a receive method for managingcommunication operations in the OFDM system, according to an embodimentas disclosed herein. The operations (502-514) are performed by thesecond OFDM apparatus (200).

At 502, the method includes receiving the signal comprising data and atleast one of the RS and the message from the first OFDM apparatus (100),wherein the RS and the message is repeated over the set of OFDM symbols.At 504, the method includes filtering the desired band containing atleast one of the RS and the message from the reference signal. At 506,the method includes removing the cyclic prefix from the signal. At 508,the method includes decoding at least one of the RS and the message fromthe signal with adjusting a circular shift in the set of symbol. At 510,the method includes estimating the interference by monitoringconsecutive slots or symbols for the interference. At 512, the methodincludes detecting the estimated interference in the slots or symbolsbeing monitored meets the predefined threshold set by the network entityor by the second OFDM apparatus (200). At 514, the method includesmitigating the interference by performing one of adjusting the GP,adjusting the UL power, adjusting the DL power, switching to the BWP,tilting a direction of the beam to avoid interference, and nullifyingthe beam in the direction of incoming interference.

FIG. 5D illustrates receiver chain with respect to the RS, according toembodiments as disclosed herein. The receiver chain is shown in FIG. 5Dwith respect to RS as an example. During reception, the receiving nodefilters the desired band containing the required signal.

FIG. 5E illustrates a receiver processing samples, according toembodiments as disclosed herein. For receiver processing, samplesequivalent to one OFDM symbol duration (of size N_(FFT) ^(R)) is takenas shown in FIG. 5E. The boundaries will not match with the exact OFDMsymbol boundaries of the transmitted signal. This is because thepropagation delay is unknown at the receiver, or due to multiplenumerology transmission. Due to the repetition inherent in the receivedtime-domain signal, the full information corresponding to onetransmitted OFDM symbol is retained. After removal of CP and taking FFTaccording to the receiver's numerology, the message is decoded. In thecase of RS, frequency domain correlation is used to detect thetransmitted sequence. The circular shift in the received symbol needs tobe determined and compensated to detect the original transmittedinformation as given in equation (2). R is the received symbol in thefrequency domain, N_(FFT) ^(R) is the FFT size at receiver and LShift isthe circular shift.

$\begin{matrix}{X_{i} = {R_{i}e^{\frac{{- j}\; 2\;\pi\; m\;{i{({L + L_{shift}})}}}{N_{FFT}^{R}}}}} & (2)\end{matrix}$

FIG. 6 illustrates transmit and receive chain for RS transmission inhigher numerology as compared to reception, according to embodiments asdisclosed herein.

In this case, the transmission of RS or broadcast message will be as insection “Repetition of information over ‘M’ symbols” whereas for thereception, after FFT, down-sampling is done with a down-sampling factorequal to the ratio of numerology of transmission to the numerology ofreception. The IFFT size at the transmitter will be according totransmitter numerology and FFT size at a receiver according to receivernumerology. The circular shift in the received symbol needs to bedetermined and compensated to detect the originally transmittedinformation as given in equation (2). For e.g. In FIG. 6, thetransmitter and receiver chains for 30 kHz and 15 kHz are shownrespectively for RS.

FIG. 7 illustrates transmit and receive chain for RS transmission inlower numerology as compared to reception, according to embodiments asdisclosed herein.

In this case, transmitter transmits the RS or broadcast message incomb-like structure (interleaved frequency division multiple access(IFDMA)) with a repetition factor equal to the ratio of numerology ofreception to the numerology of transmission. The IFFT size at thetransmitter will be according to transmitter numerology and FFT size ata receiver according to receiver numerology. The circular shift in thereceived symbol needs to be determined and compensated to detect theoriginally transmitted information as given in equation (2). For e.g. inFIG. 7, the transmitter and receiver chains for 15 kHz and 30 kHz areshown respectively for RS.

FIG. 8 illustrates a slot structure of four base stations (BS) to aid aninterference measurement, according to embodiments as disclosed herein.

In Management of interference using RS designed for asynchronousdetection,

(a) Detection of Interference Occurrence and Measurement:

A node transmits RS as described in the previous section, which isdetected at the receiving nodes to either find out the interfering nodeor measure the level of interference or both. To find out theinterfering node, the sequence generated for RS should convey the nodeID. Across different nodes, the RS sequence can be transmittedorthogonally in code, frequency, and time or space domain. In anembodiment, the nodes exchange information regarding the transmissionand reception of RS in case of multiple interfering nodes to bedetected. For e.g., the time domain orthogonality is achieved in 2 ways:(i) only one node transmits RS at one instant while all the other nodesare receiving. (ii) Only one node receives RS at one instant while allthe other nodes are transmitting. In both cases, the exchange ofinformation among the nodes is necessary. A node should know at whatinstant it should transmit RS and the symbols in which it shouldmonitor/measure RS from other nodes.

As an example, FIG. 8 shows the slot structure of 14 OFDM symbols as inNR of 4 BSs BS1, BS2, BS3, BS4 participating in interferencemeasurement. D, U and X stand for DL, UL and flexible symbolsrespectively. The flexible symbol means that the symbol will beconfigured dynamically to either UL or DL or reserved (neither UL norDL). XU represents special UL where RS is monitored/measured. When BS1transmits RS in DL in the first symbol, the other BSs are in either ULor flexible mode to receive and measure the RS.

Thus, the BSs should adopt the slot structure depending on thetransmission and reception of RS for interference measurement. In thiscase, symbols with D and XU need to be retained while the rest of thesymbols should be decided according to network traffic.

(b) Detection of Remote Interference Occurrence Between BSs andMeasurement:

-   -   i. At the BS during UL reception, when the interference over        Thermal (IOT), which is the interference level measured above        the thermal noise level at the receiver, is observed beyond        predefined threshold then the BS can conclude that interference        is present.    -   ii. After confirming the presence of interference, the BS        calculates the number of symbols affected in UL. To calculate        this, the BS checks the IOT value or instantaneous signal to        interference and noise ratio (SINR) or both to detect the number        of symbols affected. This will provide the approximate ring of        possible BSs causing the interference. BS reports this        information to the network.    -   iii. Network monitors the BSs for similar reports. If the victim        BS (BS that observes interference) also affects the aggressor        stations (BS which causes interference) in a similar way then        reciprocity holds true.    -   iv. Either victim or aggressor or both the BSs are configured to        transmit RS for interference measurement in a fixed measurement        window. This will be conveyed to BSs via operations,        administration, and management (OAM) entity.    -   v. RS are configured in the fixed measurement window. This        window is in terms of few symbols, or slots. It will be        configured to the node by higher layered signalling. The        measurement window is at the instant where DL to UL transition        happens. Measurement window will be overlapped with a flexible        DL-UL configuration of symbols as in NR.    -   vi. RS are transmitted at the beginning of the measurement        window and monitored in the last ‘N’ symbols of the measurement        window. ‘N’ value is configured by higher layered signal like        RRC or MAC-CE or L1 signalling like DCI.    -   vii. Sequence is generated to convey the group ID or cell ID or        node ID of the node or group of nodes transmitting the RS.    -   viii. Group of BSs use the same sequence which is less than CP        duration size. BSs can be grouped based on the radius of        distance depending on CP duration.    -   ix. Across different BSs, RS sequence orthogonality can be        achieved in code, frequency, and time and space domain.    -   x. The RS will be asynchronously received and detected. The        victim BSs will detect the aggressor BSs or vice versa.

(c) Remote Interference Mitigation:

BS will monitor a few consecutive slots for IOT. If the estimatedinterference in the symbols being monitored is beyond the predefinedthreshold set by either network or by BS, then the following actions canbe taken:

At Victim BS side:

-   -   i. Adjust the GP: Based on the number of symbols above the        threshold, the GP can be proportionally extended.    -   ii. Adjust the UL power: UL power can be adjusted such that the        UL signal strength is improved.    -   iii. Switch to another bandwidth part (BWP): BS can switch to a        different BWP to avoid the interference.    -   iv. Beam switching: Victim BS can tilt the receiving beam        vertically downwards to avoid interference.    -   v. Beam nullifying: Victim BS can create complete null in the        direction of incoming interference. The received RS can be used        to find the direction of arrival of interference.        At Aggressor BS Side:    -   i. Beam switching: Aggressor BS can adjust the direction of        transmit beam such that it reduces the interference to other        BSs.    -   ii. Adjust the GP: The GP can also be adjusted at the aggressor        BS side to minimize the interference.

(d) Termination of Remote Interference Measurement:

Termination can be performed based on different conditions.

-   -   i. If the victim BS takes corrective measure and the IOT is        reduced, then BS can release itself from the interference        management and convey the same to network.    -   ii. If the victim BS is not able to observe the RS in the        measurement period or whether the interference is below the        threshold, then it can withdraw itself from the interference        management.

The embodiments disclosed herein can be implemented using at least onesoftware program running on at least one hardware device and performingnetwork management functions to control the elements.

The foregoing description of the specific embodiments will so fullyreveal the general nature of the embodiments herein that others can, byapplying current knowledge, readily modify and/or adapt for variousapplications such specific embodiments without departing from thegeneric concept, and, therefore, such adaptations and modificationsshould and are intended to be comprehended within the meaning and rangeof equivalents of the disclosed embodiments. It is to be understood thatthe phraseology or terminology employed herein is for the purpose ofdescription and not of limitation. Therefore, while the embodimentsherein have been described in terms of preferred embodiments, thoseskilled in the art will recognize that the embodiments herein can bepracticed with modification within the spirit and scope of theembodiments as described herein.

What is claimed is:
 1. A method for data communication in an OrthogonalFrequency Division Multiplexing (OFDM) system, comprising; generating,by a first OFDM apparatus (100), a signal comprising data and at leastone of a Reference Signal (RS) and a message, wherein the signal isgenerated by: mapping the data onto frequency resources of each OFDMsymbol in a set of OFDM symbols, performing an Inverse Fourier Transformoperation (IFFT) on each of the OFDM symbol in the set of OFDM symbols,adding a Cyclic Prefix (CP) to each of the OFDM symbol in the set ofOFDM symbols, mapping at least one of the RS and the message onto thefrequency resources of the first OFDM symbol in the set of OFDM symbols,repeating at least one of the RS and the message in remaining OFDMsymbols in the set of OFDM symbols, performing an IFFT on each of theOFDM symbol in the set of OFDM symbols, and adding a block CP to the setof OFDM symbols; adding, by the first OFDM apparatus (100), the data andat least one of the RS and message in a time domain; and transmitting,by the first OFDM apparatus (100), the signal to a second OFDM apparatus(200), wherein repeating at least one of the RS and the message in theset of OFDM symbols comprises performing one of: repeating at least oneof the RS and the message in the set of OFDM symbols when numerology atthe first OFDM apparatus (100) is same as numerology at the second OFDMapparatus (200) repeating at least one of the RS and the message in theset of OFDM symbols when the numerology at the first OFDM apparatus(100) is higher than the numerology at the second OFDM apparatus (200),wherein a number of OFDM symbols in the set of OFDM symbols depends on aratio of the numerology of the first OFDM apparatus (100) to thenumerology of the second OFDM apparatus (200), and interleaving at leastone of the RS and the message in a frequency domain and repeating atleast one of the RS and the message in the set of OFDM symbols when thenumerology at the first OFDM apparatus (100) is lower than thenumerology at the second OFDM apparatus (200), wherein the interleavingis performed based on the ratio of the numerology of the first OFDMapparatus (100) to the numerology of the second OFDM apparatus (200). 2.The method of claim 1, wherein an IFFT size is determined based on atleast one of a bandwidth and the numerology used at the first OFDMapparatus (100).
 3. The method of claim 1, wherein a block CP length isobtained by scaling a CP length of an OFDM symbol by the number ofrepetitions.
 4. The method of claim 1, wherein at least one of the RSand the message is spread over a predefined bandwidth, wherein thepredefined bandwidth is in multiple of Resource Blocks (RBs) fully orpartially span over a configured bandwidth, and wherein the RBs areallocated in a consecutive manner or a continuous manner to avoidpossible contamination of reception.
 5. The method of claim 1, whereinthe set of OFDM symbols is determined as a function of at least one ofthe numerology used at the first OFDM apparatus (100), the numerologyused at the second OFDM apparatus (200), and a propagation delay.
 6. Themethod of claim 1, comprises adding a node identifier in a sequence usedfor generating the RS to identify an interference at the second OFDMapparatus (200), wherein the node identifier indicates at least one ofan interfering node, a group of interfering nodes, a cell and aninterference level.
 7. The method of claim 6, wherein the interferencelevel indicates at least one of a remote interference and a cross-linkinterference.
 8. The method of claim 6, wherein the RS is transmittedorthogonally in at least one of a code, the frequency domain, a timedomain, and a space domain across various nodes in the OFDM system,based on at least one of the node identifier and an interference leveland a number of affected symbols.
 9. The method of claim 8, wherein, inthe time domain, the orthogonality is achieved by one of a nodetransmits the RS at one-time unit while all the other nodes arereceiving the RS and a node receives the RS at one instant while allother nodes are transmitting the RS.
 10. The method of claim 6, whereinthe node identifier is associated with one of: the first OFDM apparatus(100) indicating that the first OFDM apparatus (100) is facing theinterference from the second OFDM apparatus (200); and the first OFDMapparatus (100) indicating that the first OFDM apparatus (100) is asource of interference for the second OFDM apparatus (200).
 11. Themethod of claim 7, wherein the remote interference level, at one of thefirst OFDM apparatus (100) and a group of first OFDM apparatus (100), isdetected when an Interference over Thermal (IOT) meets a predefinedthreshold, wherein the IOT is the interference level measured above athermal noise level.
 12. The method of claim 8, wherein the number ofaffected symbols in a transmission is determined at least one of thefirst OFDM apparatus (100) from the group of first OFDM apparatus (100),based on at least one of IOT value and a signal to interference plusnoise ratio (SINR).
 13. The method of claim 8, wherein the number ofaffected symbols determines the RS transmission from the first OFDMapparatus (100).
 14. The method of claim 12, wherein at least one of thefirst OFDM apparatus (100) and the second OFDM apparatus (200) isconfigured to transmit the RS in a measurement window comprising a setof one of symbols and slots determined by network based on at least oneof the interference level, and the number of affected symbols, whereinthe measurement window includes DL-to-UL transition point.
 15. Themethod of claim 14, wherein the RS is transmitted from at least of thefirst OFDM apparatus (100) and the second OFDM apparatus (200) at abeginning of the measurement window configured by the network.
 16. Themethod of claim 14, wherein the RS is received in at least one of thefirst OFDM apparatus (100) and the second OFDM apparatus (200) in thelast N symbols of the measurement window configured by the network,wherein the N symbols are configured by a higher layer.
 17. A method fordata communication in an Orthogonal Frequency Division Multiplexing(OFDM) system, comprising; generating, by a first OFDM apparatus (100),a signal comprising data and at least one of a Reference Signal (RS) anda message, wherein the signal is generated by: mapping the data on tofrequency resources of each OFDM symbol in a set of OFDM symbols,mapping at least one of the RS and the message onto frequency resourcesof the first OFDM symbol in the set of OFDM symbols, repeating at leastone of the RS and the message in remaining OFDM symbols in the set ofOFDM symbols, applying a phase rotation to at least one of the RS andthe message in each of the OFDM symbol in the set of OFDM symbols,wherein the phase rotation is a function of a symbol index and a CPlength, performing an Inverse Fourier Transform operation (IFFT) on eachof the OFDM symbol in the set of OFDM symbols, and adding a CP; andtransmitting, by the first OFDM apparatus (100), the signal to a secondOFDM apparatus (200), wherein repeating at least one of the RS and themessage in the set of OFDM symbols comprises performing one of:repeating at least one of the RS and the message in the set of OFDMsymbols when the numerology at the first OFDM apparatus (100) is same asthe numerology at the second OFDM apparatus (200), repeating at leastone of the RS and the message in the set of OFDM symbols when thenumerology at the first OFDM apparatus (100) is higher than thenumerology at the second OFDM apparatus (200), wherein a number of OFDMsymbols in the set of OFDM symbols depends on a ratio of the numerologyof the first OFDM apparatus (100) to the numerology of the second OFDMapparatus (200), and interleaving at least one of the RS and the messagein a frequency domain and repeating at least one of the RS and themessage in the set of OFDM symbols when the numerology at the first OFDMapparatus (100) is lower than the numerology at the second OFDMapparatus (200), wherein the interleaving is performed based on theratio of the numerology of the first OFDM apparatus (100) to thenumerology of the second OFDM apparatus (200).
 18. The method of claim17, wherein the phase rotation is performed to maintain a time-domaincircularity over a symbol at the second OFDM apparatus (200).
 19. Themethod of claim 17, wherein the phase rotation in at least one of the RSand the message is zero in one of a first OFDM symbol of the set of OFDMsymbols and a last OFDM symbol of the set of OFDM symbols.
 20. Themethod of claim 17, wherein at least one of the RS and the message isspread over a predefined bandwidth, wherein the predefined bandwidth isin multiple of Resource Blocks (RBs) fully or partially span over aconfigured bandwidth, and wherein the RBs are allocated in a consecutivemanner or a continuous manner to avoid possible contamination ofreception.
 21. The method of claim 17, wherein the set of OFDM symbolsis determined as a function of at least one of the numerology used atthe first OFDM apparatus (100), the numerology used at the second OFDMapparatus (200), and a propagation delay.
 22. The method of claim 17,adding a node identifier in a sequence used for generating the RS toidentify an interference at the second OFDM apparatus (200), wherein thenode identifier indicates at least one of an interfering node, a groupof interfering nodes, a cell, and an interference level.
 23. The methodof claim 22, wherein the interference is one of a remote interferenceand a cross-link interference.
 24. The method of claim 22, wherein thesequence used for generating the RS is transmitted orthogonally in atleast one of a code, the frequency domain, the time domain, and a spacedomain across various nodes in the OFDM system, based on at least one ofthe node identifier and an interference level and a number of affectedsymbols.
 25. The method of claim 24, wherein in the time domain, theorthogonality is achieved by one of a node transmits the RS at one-timeunit while all the other nodes are receiving the RS and a node receivesthe RS at one instant while all other nodes are transmitting the RS. 26.The method of claim 22, wherein the node identifier is associated withone of: the first OFDM apparatus (100) indicating that the first OFDMapparatus (100) is facing the interference from the second OFDMapparatus (200); and the interfering node indicating that theinterfering node is causing the interference at the first OFDM apparatus(100).
 27. The method of claim 23, wherein the remote interference atthe first OFDM apparatus (100) is detected when an Interference overThermal (IOT) meets a predefined threshold, wherein the IOT is theinterference level measured above a thermal noise level at the secondOFDM apparatus (200).
 28. The method of claim 24, wherein the number ofaffected symbols in a transmission is determined at, at least one of thefirst OFDM apparatus (100) from the group of first OFDM apparatus (100)based on at least one of TOT value and a signal to interference plusnoise ratio (SINR).
 29. The method of claim 24, wherein the number ofaffected symbols are included in the at least one RS.
 30. The method ofclaim 29, wherein the at least one RS are configured in a fixedmeasurement window in terms of symbols or slots, and wherein themeasurement window derived at a point where one of a DL-to-UL transitionor a DL-to-UL transition occurs.
 31. The method of claim 29, wherein theat least one RS is reported at a beginning of the measurement window.32. A method for data communication in an Orthogonal Frequency DivisionMultiplexing (OFDM) system, comprising; receiving, by a second OFDMapparatus (200), a signal comprising data and at least one of aReference Signal (RS) and a message from a first OFDM apparatus (100),wherein the RS and the message is repeated over a set of OFDM symbols;filtering, by the second OFDM apparatus (200), a desired band containingat least one of the RS and the message from the received signal;removing, by the second OFDM apparatus (200), a cyclic prefix (CP) fromthe filtered signal; and decoding, by the second OFDM apparatus (200),at least one of the RS and the message from the signal with adjusting acircular shift in the set of symbol, wherein the circular shift is afunction of a propagation delay, a numerology of the first OFDMapparatus (100) and a numerology of the second OFDM apparatus (200). 33.The method of claim 32, wherein a circular shift in the set of symbol isdetermined and compensated to detect original transmitted informationfrom the signal when a frequency domain correlation is used to detect asequence of the RS.
 34. The method of claim 32, wherein decoding atleast one of the RS and the message from the signal is performed usingthe FFT operation according to the numerology of the second OFDMapparatus (200).
 35. The method of claim 32, comprising determining atleast one of an interfering node and an interference level based on anode identifier indicated in a sequence used for generating the RS. 36.The method of claim 32, wherein at least one of the RS and the messageis spread over a predefined bandwidth, wherein the predefined bandwidthis in multiple of group of Resource Blocks (RBs) fully or partially spanover a configured bandwidth, wherein the group of RBs are allocated in aconsecutive manner or a continuous manner to avoid possiblecontamination of reception.
 37. The method of claim 32, wherein the setof OFDM symbols is determined as a function of at least one of thenumerology used at the first OFDM apparatus (100), the numerology usedat the second OFDM apparatus (200), and a propagation delay.
 38. Themethod of claim 35, wherein the node identifier is associated with oneof: the first OFDM apparatus (100) indicating that the first OFDMapparatus (100) is facing the interference from the second OFDMapparatus (200); and the interfering node indicating that theinterfering node is causing the interference at the first OFDM apparatus(100).
 39. The method of claim 32, wherein the method further comprises:estimating, by the second OFDM apparatus (200), the interference bymonitoring consecutive slots or symbols for the interference; detecting,by the second OFDM apparatus (200), the estimated interference in theslots or symbols being monitored meets a predefined threshold set by anetwork entity or by the second OFDM apparatus (200); and mitigating, bythe second OFDM apparatus (200), the interference by performing one ofadjusting a Guard Period (GP), adjusting a UL power, adjusting a DLpower, switching to a bandwidth part (BWP), tilting a direction of abeam to avoid interference, and nullifying a beam in a direction ofincoming interference.
 40. The method of claim 39, wherein the methodfurther comprises terminating the estimation of the interference whenthe second OFDM apparatus (200) is not able to observe the at least oneRS in a measurement period.
 41. A first OFDM apparatus (100) for datacommunication in an Orthogonal Frequency Division Multiplexing (OFDM)system, comprising: a memory (110); and a processor (120), operationallycoupled to the memory (110) configured to: generate a signal comprisingdata and at least one of a Reference Signal (RS) and a message, whereinthe signal is generated by: map the data onto frequency resources ofeach OFDM symbol in a set of OFDM symbols, perform an Inverse FourierTransform operation (IFFT) on each of the OFDM symbol in the set of OFDMsymbols, add a Cyclic Prefix (CP) to each of the OFDM symbol in the setof OFDM symbols, map at least one of the RS and the message onto thefrequency resources of the first OFDM symbol in the set of OFDM symbols,repeat at least one of the RS and the message in remaining OFDM symbolsin the set of OFDM symbols, perform an IFFT on each of the OFDM symbolin the set of OFDM symbols, add a block CP to the set of OFDM symbols;add the data and at least one of the RS and the message in a timedomain; and transmit the signal to a second OFDM apparatus (200),wherein repeat at least one of the RS and the message in the set of OFDMsymbols comprises performing one of: repeat at least one of the RS andthe message in the set of OFDM symbols when numerology at the first OFDMapparatus (100) is same as numerology at the second OFDM apparatus(200), repeat at least one of the RS and the message in the set of OFDMsymbols when the numerology at the first OFDM apparatus (100) is higherthan the numerology at the second OFDM apparatus (200), wherein a numberof OFDM symbols in the set of OFDM symbols depends on a ratio of thenumerology of the first OFDM apparatus (100) to the numerology of thesecond OFDM apparatus (200), and interleave at least one of the RS andthe message in a frequency domain and repeating at least one of the RSand the message in the set of OFDM symbols when the numerology at thefirst OFDM apparatus (100) is lower than the numerology at the secondOFDM apparatus (200), wherein the interleaving is performed based on theratio of the numerology of the first OFDM apparatus (100) to thenumerology of the second OFDM apparatus (200).
 42. The first OFDMapparatus (100) of claim 41, wherein an IFFT size is determined based onat least one of a bandwidth and the numerology used at the first OFDMapparatus (100).
 43. The first OFDM apparatus (100) of claim 41, whereina block CP length is obtained by scaling a CP length of an OFDM symbolby the number of repetitions.
 44. The first OFDM apparatus (100) ofclaim 41, wherein at least one of the RS and the message is spread overa predefined bandwidth, wherein the predefined bandwidth is in multipleof Resource Blocks (RBs) fully or partially span over a configuredbandwidth, and wherein the RBs are allocated in a consecutive manner ora continuous manner to avoid possible contamination of reception. 45.The first OFDM apparatus (100) of claim 41, wherein the set of OFDMsymbols is determined as a function of at least one of the numerologyused at the first OFDM apparatus (100), the numerology used at thesecond OFDM apparatus (200), and a propagation delay.
 46. The first OFDMapparatus (100) of claim 41, wherein the processor (120) is configuredfor adding a node identifier in a sequence used for generating the RS toidentify an interference at the second OFDM apparatus (200), wherein thenode identifier indicates at least one of an interfering node, a groupof interfering nodes, a cell and an interference level.
 47. The firstOFDM apparatus (100) of claim 46, wherein the interference levelindicates at least one of a remote interference and a cross-linkinterference.
 48. The first OFDM apparatus (100) of claim 46, whereinthe RS is transmitted orthogonally in at least one of a code, thefrequency domain, a time domain, and a space domain across various nodesin the OFDM system, based on at least one of the node identifier and aninterference level and a number of affected symbols.
 49. The first OFDMapparatus (100) of claim 48, wherein, in the time domain, theorthogonality is achieved by one of a node transmits the RS at one-timeunit while all the other nodes are receiving the RS and a node receivesthe RS at one instant while all other nodes are transmitting the RS. 50.The first OFDM apparatus (100) of claim 46, wherein the node identifieris associated with one of: the first OFDM apparatus (100) indicatingthat the first OFDM apparatus (100) is facing the interference from thesecond OFDM apparatus (200); and the first OFDM apparatus (100)indicating that the first OFDM apparatus (100) is a source ofinterference for the second OFDM apparatus (200).
 51. The first OFDMapparatus (100) of claim 47, wherein the remote interference level, atone of the first OFDM apparatus (100) and a group of first OFDMapparatus (100), is detected when an Interference over Thermal (IOT)meets a predefined threshold, wherein the IOT is the interference levelmeasured above a thermal noise level.
 52. The first OFDM apparatus (100)of claim 48, wherein the number of affected symbols in a transmission isdetermined at, at least one of the first OFDM apparatus (100) from thegroup of first OFDM apparatus (100) based on at least one of IOT valueand a signal to interference plus noise ratio (SINR).
 53. The first OFDMapparatus (100) of claim 48, wherein the number of affected symbolsdetermines the RS transmission from the first OFDM apparatus (100). 54.The first OFDM apparatus (100) of claim 52, wherein at least one of thefirst OFDM apparatus (100) and the second OFDM apparatus (200) isconfigured to transmit the RS in a measurement window comprising a setof one of symbols and slots determined by network based on at least oneof the interference level, and the number of affected symbols, whereinthe measurement window includes DL-to-UL transition point.
 55. The firstOFDM apparatus (100) of claim 54, wherein the RS is transmitted from atleast of the first OFDM apparatus (100) and the second OFDM apparatus(200) at a beginning of the measurement window configured by thenetwork.
 56. The first OFDM apparatus (100) of claim 54, wherein the RSis received in at least one of the first OFDM apparatus (100) and thesecond OFDM apparatus (200) in the last N symbols of the measurementwindow configured by the network, wherein the N symbols are configuredby a higher layer.
 57. A first OFDM apparatus (100) for datacommunication in an Orthogonal Frequency Division Multiplexing (OFDM)system, comprising: a memory (110); and a processor (120), operationallycoupled to the memory (110) configured to: generate a signal comprisingdata and at least one of a Reference Signal (RS) and a message, whereinthe signal is generated by: map the data on to frequency resources ofeach OFDM symbol in a set of OFDM symbols, map at least one of the RSand the message onto frequency resources of the first OFDM symbol in theset of OFDM symbols, repeat at least one of the RS and the message inremaining OFDM symbols in the set of OFDM symbols, applying a phaserotation to at least one of the RS and the message in each of the OFDMsymbol in the set of OFDM symbols, wherein the phase is a function of asymbol index and a CP length, perform an Inverse Fourier Transformoperation (IFFT) in each of the OFDM symbol in the set of OFDM symbols,and add a CP; and transmit the signal to a second OFDM apparatus (200),wherein repeat at least one of the RS and the message in the set of OFDMsymbols comprises performing one of: repeat at least one of the RS andthe message in the set of OFDM symbols when the numerology at the firstOFDM apparatus (100) is same as the numerology at the second OFDMapparatus (200), repeat at least one of the RS and the message in theset of OFDM symbols when the numerology at the first OFDM apparatus(100) is higher than the numerology at the second OFDM apparatus (200),wherein a number of OFDM symbols in the set of OFDM symbols depends on aratio of the numerology of the first OFDM apparatus (100) to thenumerology of the second OFDM apparatus (200), and interleave at leastone of the RS and the message in a frequency domain and repeating atleast one of the RS and the message in the set of OFDM symbols when thenumerology at the first OFDM apparatus (100) is lower than thenumerology at the second OFDM apparatus (200), wherein the interleavingis performed based on the ratio of the numerology of the first OFDMapparatus (100) to the numerology of the second OFDM apparatus (200).58. The first OFDM apparatus (100) of claim 57, wherein the phaserotation is performed to maintain a time-domain circularity over asymbol at the second OFDM apparatus (200).
 59. The first OFDM apparatus(100) of claim 57, wherein the phase rotation in at least one of the RSand the message is zero in one of a first OFDM symbol of the set of OFDMsymbols and a last OFDM symbol of the set of OFDM symbols.
 60. The firstOFDM apparatus (100) of claim 57, wherein at least one of the RS and themessage is spread over a predefined bandwidth, wherein the predefinedbandwidth is in multiple of Resource Blocks (RBs) fully or partiallyspan over a configured bandwidth, and wherein the RBs are allocated in aconsecutive manner or a continuous manner to avoid possiblecontamination of reception.
 61. The first OFDM apparatus (100) of claim57, wherein the set of OFDM symbols is determined as a function of atleast one of the numerology used at the first OFDM apparatus (100), thenumerology used at the second OFDM apparatus (200), and a propagationdelay.
 62. The first OFDM apparatus (100) of claim 57, adding a nodeidentifier in a sequence used for generating the RS to identify aninterference at the second OFDM apparatus (200), wherein the nodeidentifier indicates at least one of an interfering node, a group ofinterfering nodes, a cell, and an interference level.
 63. The first OFDMapparatus (100) of claim 62, wherein the interference is one of a remoteinterference and a cross-link interference.
 64. The first OFDM apparatus(100) of claim 62, wherein the sequence used for generating the RS istransmitted orthogonally in at least one of a code, the frequencydomain, the time domain, and a space domain across various nodes in theOFDM system, based on at least one of the node identifier and aninterference level and a number of affected symbols.
 65. The first OFDMapparatus (100) of claim 64, wherein in the time domain, theorthogonality is achieved by one of a node transmits the RS at one-timeunit while all the other nodes are receiving the RS and a node receivesthe RS at one instant while all other nodes are transmitting the RS. 66.The first OFDM apparatus (100) of claim 62, wherein the node identifieris associated with one of: the first OFDM apparatus (100) indicatingthat the first OFDM apparatus (100) is facing the interference from thesecond OFDM apparatus (200); and the interfering node indicating thatthe interfering node is causing the interference at the first OFDMapparatus (100).
 67. The first OFDM apparatus (100) of claim 63, whereinthe remote interference at the first OFDM apparatus (100) is detectedwhen an Interference over Thermal (IOT) meets a predefined threshold,wherein the IOT is the interference level measured above a thermal noiselevel at the second OFDM apparatus (200).
 68. The first OFDM apparatus(100) of claim 64, wherein the number of affected symbols in atransmission is determined at, at least one of the first OFDM apparatus(100) from the group of first OFDM apparatus (100) based on at least oneof IOT value and a signal to interference plus noise ratio (SINR). 69.The first OFDM apparatus (100) of claim 64, wherein the number ofaffected symbols are included in the at least one RS.
 70. The first OFDMapparatus (100) of claim 69, wherein the at least one RS are configuredin a fixed measurement window in terms of symbols or slots, and whereinthe measurement window derived at a point where one of a DL-to-ULtransition or a DL-to-UL transition occurs.
 71. The first OFDM apparatus(100) of claim 69, wherein the at least one RS is reported at abeginning of the measurement window.
 72. A second OFDM apparatus (200)for data communication in an Orthogonal Frequency Division Multiplexing(OFDM) system, comprising: a memory (210); and a processor (220),operationally coupled to the memory (210) configured to: receive asignal comprising data and at least one of a Reference Signal (RS) and amessage from a first OFDM apparatus (100), wherein the RS and themessage is repeated over a set of OFDM symbols; filter a desired bandcontaining at least one of the RS and the message from the referencesignal; remove a cyclic prefix (CP) from the signal; and decode at leastone of the RS and the message from the signal with adjusting a circularshift in the set of symbol, wherein the circular shift is a function ofa propagation delay, a numerology of the first OFDM apparatus (100) anda numerology of the second OFDM apparatus (200).
 73. The second OFDMapparatus (200) of claim 72, wherein the circular shift in the set ofsymbol is determined and compensated to detect original transmittedinformation from the signal when a frequency domain correlation is usedto detect a sequence of the RS.
 74. The second OFDM apparatus (200) ofclaim 72, wherein decoding at least one of the RS and the message fromthe signal is performed using the FFT operation according to thenumerology of the second OFDM apparatus (200).
 75. The second OFDMapparatus (200) of claim 72, wherein the processor (220) configured fordetermining at least one of an interfering node and an interferencelevel based on a node identifier indicated in a sequence used forgenerating the RS.
 76. The second OFDM apparatus (200) of claim 72,wherein at least one of the RS and the message is spread over apredefined bandwidth, wherein the predefined bandwidth is in multiple ofgroup of Resource Blocks (RBs) fully or partially span over a configuredbandwidth, wherein the group of RBs are allocated in a consecutivemanner or a continuous manner to avoid possible contamination ofreception.
 77. The second OFDM apparatus (200) of claim 72, wherein theset of OFDM symbols is determined as a function of at least one of thenumerology used at the first OFDM apparatus (100), the numerology usedat the second OFDM apparatus (200), and a propagation delay.
 78. Thesecond OFDM apparatus (200) of claim 75, wherein the node identifier isassociated with one of: the first OFDM apparatus (100) indicating thatthe first OFDM apparatus (100) is facing the interference from thesecond OFDM apparatus (200); and the interfering node indicating thatthe interfering node is causing the interference at the first OFDMapparatus (100).
 79. The second OFDM apparatus (200) of claim 72,wherein the method further comprises: estimating, by the second OFDMapparatus (200), the interference by monitoring consecutive slots orsymbols for the interference; detecting, by the second OFDM apparatus(200), the estimated interference in the slots or symbols beingmonitored meets a predefined threshold set by a network entity or by thesecond OFDM apparatus (200); and mitigating, by the second OFDMapparatus (200), the interference by performing one of adjusting a GuardPeriod (GP), adjusting a UL power, adjusting a DL power, switching to abandwidth part (BWP), tilting a direction of a beam to avoidinterference, and nullifying a beam in a direction of incominginterference.
 80. The second OFDM apparatus (200) of claim 79, whereinthe method further comprises terminating the estimation of theinterference when the second OFDM apparatus (200) is not able to observethe at least one RS in a measurement period.